Check out this smart, funny, and creative use of promotional sticky notes. Oral-B, the makers of popular teeth whitening products, created custom Post It-style notes that fade from dingy yellow to sparkling white as you use more and more of them. By the time you get to the last note, no trace of yellow remains. There’s something about the simplicity of this promotion that I really admire – it’s a major achievement when you can come up with something this creative using a common product that people use every day.